This invention relates to digital versatile disks (DVD), also known as digital video disks. More particularly, the present invention relates to the portion of the DVD formatting standard that allows for storage of multiple angles of the same video scene. A new and improved apparatus and method is provided for simultaneously displaying more than one such angle in a DVD video playback on a television or monitor.
The digital versatile disk (DVD) standards provide for many features that were not available in previous standard video technologies, such as VHS tape and laser disc. Such additional features include the ability to allow the user to interact with the playback of DVD audio/visual (A/V) content to customize the presentation of the DVD A/V content for the user""s preferences. The author of the DVD A/V content, however, must enable many of these features in the DVD A/V content for the features to be available to the user. For example, the author may choose to incorporate subtitles in DVD A/V content, and the user can choose which language, if any, in which to view the subtitles. An author may also re-film or reedit some scenes of a motion picture in different manners, such as to achieve any desired rating by the Motion Picture Association of America (e.g. NC-17, R, PG-13, PG or G). The author may then include each different version of the scenes in the DVD A/V content with formatting for xe2x80x9cparentalxe2x80x9d control which causes the playback of the motion picture to branch between scenes so as to present only the version with the desired rating. The user may select which version or which scenes to view. A DVD A/V content author may also shoot some scenes of a motion picture from multiple angles and incorporate all of the angles, up to nine angles, in the DVD A/V content for the user to select which angle of the scene to view. Blocks of digital data for the angles are interleaved together onto the DVD disk so that the playback can branch between scenes with seamless A/V playback.
A manufacturer or developer of a DVD player, or DVD equipment in a computer, must enable each of these features in the DVD player for the user to be able to access them. In other words, the hardware, firmware and software must be present in the DVD player for the DVD player to be able to recognize the features that the author has incorporated in the DVD content and to permit the user to select from among these features. The enabling hardware, firmware and software of the DVD player must be able to decode raw bitstream data from the DVD disk for the full complement of standard DVD features to identify the particular features of the DVD content.
DVD players enabled for viewing multiple angles of video scenes provide a remote control unit (RCU) menu to use for selecting which angle to view. The RCU menu may include buttons on a physical unit and/or icons in a graphical menu displayed on a display screen. Typically, the user selects which angle to view for one or more scenes and then views the playback of the selected angle for each scene. If the user wants to view more than one angle for a given scene, then the user waits until the first angle finishes playing and then returns to the RCU menu to select and play the next angle. Only one angle at a time may be viewed, since DVD players do not have the capability to decode the raw bitstream data from the DVD disk for more than one angle at a time.
Additionally, a single audio track may be included by the author to synchronize with all of the angles, in which case the user does not select from among different audio tracks. Instead, the single audio track plays along with any selected angle. Alternatively, each angle may have its own separate audio track, in which case the user""s selection of the video angle also selects the audio track for that angle.
It is with respect to these and other background considerations that the present invention has evolved.
The present invention relates to a new and improved method and apparatus for accessing DVD A/V content that permits simultaneous viewing of more than one video angle. The user selects parameters for viewing any number of angles from the available angles, up to nine. Video frames for the selected angles are scaled down in size, after being decoded, to fit into a section or fragment of the display screen, and the scaled frames are assembled into a single frame for presentation on the display screen. In addition, if more than one audio track is available for the angles, the user also selects which angle""s audio track is played with the video playback. In this manner, the user does not have to stop the video playback after viewing one angle of a scene to return to the RCU menu to select the next angle to view. Rather, the user makes all angle and audio selections at once in an RCU menu and then views a side-by-side presentation of each selected angle. Alternatively, preset parameters may be selected by the user or selected automatically.
These and other improvements are achieved in a method for playing DVD content having multiple angles of video wherein frames of DVD video are decoded for each angle, and the decoded frames for each angle are simultaneously displayed in a display TV or monitor. Preferably, the display area is fragmented, and each display fragment is correlated to one of the angles, so the decoded frames for each angle are displayed in one of the display fragments. The decoded frames also are preferably filtered down to a size that corresponds to the size of the display fragments, so the filtered frames may be assembled into a single presentable frame that is viewed on the display.
The previously mentioned and other improvements are also achieved in a method of controlling playback of DVD content having multiple angles of video wherein a plurality of desired angles are selected for playback and are simultaneously displayed on a display TV or monitor. The fragmentation of the display is preferably selected so each of the desired angles is displayed in a display fragment. The correlation between the display fragments and the desired angles is also preferably selected. An audio track may also preferably be selected to accompany the playback of the video.
The previously mentioned and other improvements are also achieved in a DVD player for playing back DVD content that contains multiple angles of video. The DVD player comprises a decoder and an assembling unit. The decoder is operable to receive a bitstream for each angle and to multiplex between each angle""s bitstream to decode a portion of the bitstream for each angle into frames for each angle. The assembling unit is operably connected to the decoder to receive the decoded frames for each angle and assemble the decoded frames into presentable frames that contain a frame for each angle. The presentable frames can be displayed on the display to simultaneously present the multiple angles of video.
The DVD player preferably further comprises a filter that is operably connected to the decoder and the assembling unit to receive the decoded frames for each angle and filter the decoded frames for each angle to a size corresponding to a fragment of the display. The presentable frames are, thus, assembled by placing the filtered frames into areas of the presentable frames that correspond to the display fragments, preferably without overlapping the filtered frames. The DVD player also preferably further comprises a frame store unit that is operably connected to the decoder and the filter to receive the decoded frames one at a time and provide the decoded frames to the filter in parallel.